Nassau police arrest man after North Massapequa homicide probe

Nassau County police arrested Joseph Horner, 27, on a second-degree murder charge Tuesday after a family disturbance call Monday at a North Massapequa home on Long Island left 25-year-old Victoria Castle dead. Detectives shut down streets for 12 hours while gathering evidence outside 285 North Oak Street.

What began as a reported family disturbance in a quiet Nassau County neighborhood escalated into a homicide investigation that drew a heavy police presence along North Oak Street and nearby Magnolia Drive. By Tuesday, authorities had made an arrest, identified the victim, and prepared updates from police headquarters in Mineola.

For Long Island communities built around suburban stability, sudden violent crime in a residential area raises immediate questions about safety and accountability. Here is what Nassau County police and local reporting have confirmed so far.

Key Takeaways

• Police responded around 8:45 a.m. Monday, June 29, 2026, to 285 North Oak Street after Joseph Horner called 911 requesting an ambulance for a female victim.
• Investigators found 25-year-old Victoria Castle unresponsive in a ground-floor apartment; she was pronounced dead at 9:25 a.m. at a local hospital.
• Horner, an Oceanside School District music teacher who lived upstairs with his wife, was charged with second-degree murder and faces up to 25 years to life if convicted.
• Police shut down the neighborhood for roughly 12 hours Monday, towed a vehicle around 9 p.m., and later reopened North Oak Street and Magnolia Drive.
• Officials said the case has no connection to the school district or its students; Horner was placed on administrative leave.

What Happened at the North Massapequa Home on Monday?

According to Nassau County police and News 12 Long Island, officers were dispatched to 285 North Oak Street shortly before 9 a.m. Monday after Horner reported that a woman needed medical help. Police found Horner outside the residence when they arrived.

The property is a multi-family home split into two apartments. Horner and his wife lived upstairs; Castle, his wife's sister, lived on the ground level. Officials initially described the incident as a family disturbance that left one person injured before treating it as a homicide investigation.

Inside the ground-floor unit, officers located Castle on the floor, administered lifesaving medical assistance, and transported her to a hospital, where she was pronounced dead at 9:25 a.m. Investigators determined the cause of death was strangulation based on the scene and the victim's injuries.

For much of Monday, detectives examined the driveway, collected evidence, and kept surrounding streets closed. Around 9 p.m., Nassau County police towed a vehicle parked in front of the home before clearing the scene and reopening roads.

Who Is Joseph Horner and What Charges Does He Face?

Nassau County police arrested Horner, 27, of North Massapequa, and charged him with one count of second-degree murder. If convicted, he faces up to 25 years to life in prison.

At a Tuesday briefing, Detective Lieutenant Daniel Steller said Horner called 911 at 8:44 a.m. Monday requesting police and an ambulance to the North Oak Street address for a deceased female. After interviewing Horner, police located Castle in the first-floor apartment.

Police said Horner acted alone. His wife was not home and was not involved. The couple had been married for about three years and shared the upstairs apartment, according to investigators.

Horner pleaded not guilty at his arraignment and was held without bail, News 12 reported. His attorney described him as a tenured teacher well regarded by students and colleagues.

What Did Prosecutors Allege at Horner's Arraignment?

At the arraignment, a Nassau County prosecutor said Horner had harbored a sexual desire toward his sister-in-law and saw an opportunity while his wife was away, according to News 12. The prosecutor alleged Horner asked Castle to help move a piano, then attacked her without warning and placed her in a chokehold until her body went limp.

Prosecutors further alleged Horner sexually assaulted Castle before changing his clothes and calling 911. News 12 reported Horner later admitted to authorities that he had choked her and then had sex with her. Police at the Tuesday briefing had previously declined to disclose a motive.

Castle was a 25-year-old Massapequa resident and Ph.D. student at Stony Brook University. Police said Horner had known her since 2016, when he first met his wife. No one involved had a prior criminal record, Steller said.

How Did the Oceanside School District Respond?

Horner is employed as a music teacher in the Oceanside School District, officials confirmed. Police said the incident had no relation to the school system.

Superintendent Phyllis Harrington said Nassau County officials indicated the homicide charges have no connection to the district or its students, News 12 reported. Harrington said Horner was placed on administrative leave effective immediately, pending further review.

For parents on Long Island, the distinction matters: police stressed the alleged crime occurred at a private residence, not on campus. Still, the arrest of a tenured educator has drawn wide attention across Nassau County.

What Should Long Island Residents Know Next?

Detective Lieutenant Steller acknowledged the large police presence created fear and confusion in the Massapequa community. He thanked residents for their patience and said he wanted to reassure the neighborhood that it remains safe.

Multi-family homes like the split-level property on North Oak Street are common across Long Island, where relatives sometimes share adjoining units. Anyone following Long Island lifestyle and community news knows neighborhood stability often shapes where families choose to live and work.

Police have not named additional suspects. The case now moves through the Nassau County court system, where Horner entered a not-guilty plea and was denied bail. News 12, Patch, and Herald Community Newspapers continue to cover developments as authorities release further information.